Rectal bleeding is the passage of blood from the bottom. Most rectal bleeding is not a cause for concern. In some cases, however, the rectal bleeding can be heavy, troublesome or linked to a more serious condition such as bowel cancer. We answer your frequently asked questions about rectal bleeding.
What is rectal bleeding?
Rectal bleeding is the passage of blood from the bottom. Despite its name, rectal bleeding may be from the:
- anal canal (the opening from your large bowel to the outside, just inside your bottom)
- rectum (the last part of the large bowel that holds poo, before it passes out of the body)
- any other part of the large bowel (higher up than the rectum)
Rectal bleeding is common and likely to affect everyone at some stage in their life. Thankfully, most rectal bleeding is not a cause for concern. In some cases, however, the rectal bleeding can be heavy, troublesome or linked to a more serious condition such as bowel cancer.
What causes rectal bleeding?
The most common cause of rectal bleeding is the passage of blood from haemorrhoids (piles). These are enlarged blood vessels inside your bottom. Some people are more likely to get haemorrhoids than others. They are usually caused by straining (such as from constipation or childbirth) or from sitting on the toilet for too long.
The most serious cause of rectal bleeding is bowel cancer. This is one of the most common cancers and the risk of developing it increases as you get older. Although the condition can run in families, it usually affects individuals who have no family history of bowel cancer.
Rectal bleeding can also arise from inflammation (redness and swelling) of the bowel. This inflammation can be caused by gut infections or inflammatory bowel disease (IBD). Other common causes of rectal bleeding are:
- an anal fissure, which is a tear in the lining of the anus
- diverticular change, which is a type of wear and tear that, with age, occurs in almost everyone’s bowel
What are the signs and symptoms of rectal bleeding?
The signs and symptoms of rectal bleeding are as follows:
- Haemorrhoids: Bleeding from haemorrhoids tends to be bright red and painless. It is often seen when you wipe your bottom but can also drip into the toilet bowl. You may also have a prolapsing lump (a lump or swelling that comes out of your bottom), itching and constipation.
- Bowel cancer and inflammatory conditions: These conditions tend to cause darker rectal bleeding that can be mixed with your poo. You may also have a change in bowel habit, often with looser poo, and a need to empty your bowel more frequently.
- Anal fissures: The bleeding from anal fissures is accompanied by severe pain in the bottom. You usually notice spots of blood on the toilet paper.
- Diverticular change: Bleeding from diverticular change (when small bulges or pockets develop in the lining of the large bowel) often occurs in older people. This condition usually causes no symptoms, but can result in the passage of a large amount of blood.
Are there any tests for rectal bleeding?
If you have new symptoms of rectal bleeding that are persistent and unexplained, it is important to get medical advice. Your doctor will ask you some questions about your symptoms and examine your bottom. They can then give you advice on how best to manage your bleeding.
If necessary, your doctor may refer you to a bowel specialist. The specialist can arrange for you to have a short camera test called a flexible sigmoidoscopy. This allows them to examine the rectum and nearby colon (the lower part of the large bowel). Before this test, an enema (or cleansing medicine) is given to clear your bowel of poo.
In some cases, you may need a full colonoscopy. With this procedure, your specialist can examine the whole of the large bowel. You need to take bowel cleansing medicine that you swallow and avoid eating before the test. This ensures that your bowel is empty and can be examined. Colonoscopy is usually performed with sedation. This means that you are given medicine to make you feel relaxed and sleepy.
How is rectal bleeding treated?
Your treatment depends on what is causing the rectal bleeding:
Rectal bleeding caused by haemorrhoids
If your rectal bleeding is caused by haemorrhoids, your doctor will usually recommend that you make changes to your diet and toileting habits. Try to eat plenty of fibre and drink enough water. Fibre is found in fruit, vegetables, pulses and grains, such as wholemeal bread and cereals.
If your poos are still hard, infrequent or difficult to pass, you may consider taking a gentle laxative. This is a type of medicine that can soften the poo and encourage it to be passed. It is important to avoid straining when you poo and sitting on the toilet for long periods.
A bowel specialist can recommend suitable treatment if your bleeding is troublesome. For example, medicine can be injected directly into haemorrhoids to make them shrink. Alternatively, a small rubber band can be placed around the haemorrhoids to strangle them and make them drop off. If these procedures do not help, you may need surgery to treat the haemorrhoids. There are different types of surgery, including:
- Haemorrhoidopexy: This is an operation to cut off the blood supply to the haemorrhoids and move them into a normal position. In the HALO procedure (a Haemorrhoidal Artery Ligation Operation), the arteries to the haemorrhoids are tied. That reduces the blood supply to the haemorrhoids and helps them to shrink. In the Rafaelo procedure (Radio Frequency Ablation of Haemorrhoids under Local Anaesthetic), radio waves are used to reduce the blood supply to the haemorrhoids and make them shrink.
- Haemorrhoidectomy: This is the traditional operation that is used to cut out and remove haemorrhoids.
Rectal bleeding due to another condition
If your rectal bleeding is due to another condition, your specialist will manage the bleeding by treating the underlying cause. For example, inflammatory bowel conditions can be treated with medicines that reduce inflammation. In the case of bowel cancer, surgery is usually performed to remove the cancer.